This invention relates generally to fluid emulsification systems and methods, including fluid delivery systems for combustion engines and similar applications, including gas, diesel and jet engines. More specifically, this invention also relates to systems and methods that promote uniform and homogenous emulsification of a liquid (such as fuel) by blending a gas (such as air) with the liquid and then supplying this blended mixture to an engine. One application of the invention is in fuel delivery systems, such as used for internal combustion (including gas and diesel engines) or jet engines, where thorough and homogeneous emulsification of the fuel and air, and the supply of this mixture in augmentation of a primary fuel supply system, results in greatly increased engine efficiency. Also disclosed are improvements in carburetor fuel passages, including the relative positioning of boosters and venturis in carburetors and other flow enhancing attachments that have an effect on booster and overall carburetor efficiency.
Emulsification of a fluid stream occurs by introducing air or gas into the fluid stream, and is beneficial in many applications. For example, it is known to form an emulsion of air with fuel flowing to the carburetor of an internal combustion engine, with the benefit of increasing the efficiency of combustion. The more homogeneous and complete the air is emulsified with the fuel, the more efficient the combustion process will be. Combustion that is more efficient results in better performance with reduced pollution and emissions. Emulsification of a fuel charge with air is beneficial not only in standard combustion engines, but also in diesel engines and other applications such as jet engines, turbines, home heating systems, paint spraying, perfume dispensing, and the like.
Many prior art systems have attempted, without success, to achieve complete fuel/air emulsification. Most of those systems relate to emulsification of fuel with air for an internal combustion engine. Some such systems attempt to emulsify the fuel downstream of the venturi region of a carburetor, while other such systems attempt emulsification within the venturi region. Still other systems attempt emulsification at the point of fuel delivery. Those prior art systems fail to completely, or homogeneously, emulsify the air and fuel mixture.
FIGS. 1 and 1A are simplified diagrams depicting a standard carburetor having a known emulsification system as used in commercially available Holley(copyright) carburetors. Several references discuss the general subject of carburetor operation. See, for example, Super Tuning and Modifying Holley Carburetors, by Dave Emanuel (S-A Design Books, E. Brea, Calif, 1988), and Holley Carburetors, by Mike Urich and Bill Fisher (HP Books, Los Angeles, Calif, 1987). Both of those books are incorporated herein by reference. Their descriptions of carburetor operation include short discussions on the importance and operation of an emulsion tube in a carburetor.
In the normal operation of a carburetor, the fuel 8 is delivered from a source 10 to a float bowl 12. A float 14 meters the amount of fuel retained in the bowl through a valve system such as a needle and seat assembly 15, The fuel enters a main well 18 through a power valve circuit 16 and/or a main jet 17. The downward stroke of a piston in the engine creates a differential between atmospheric pressure and the pressure in the engine cylinder. The pressure differential creates a partial vacuum in the venturi region 22 of a booster of the carburetor and draws the intake air 23 through the venturi of the booster as well as through the venturi in the throat or throats of the carburetor. The venturi effect in the booster causes the fuel to discharge through nozzle 20 forming a mixture 24 of ambient air and fuel. This air-fuel mixture passes through throttle valve 25 and the intake manifold system to the cylinders, where it is combusted by engine 26.
The prior art carburetor of FIGS. 1 and 1A include an emulsion tube 28 shown in communication with the main well 18 through one or more air channels or ports 30. The emulsion tube 28 obtains air from an air intake orifice 32, which is typically located upstream of the venturi portion of the carburetor. The mixing force of the air attempts to break down the fuel into an air/fuel mixture before it enters the venturi region of the carburetor. However, the mixing is not homogeneous or complete, and is only partially effective.
More specifically, the deficiency in the design of FIGS. 1 and 1A results primarily because the walls of the main well 18 and emulsion tube 28 are simple smooth walled cylinders. Therefore, the air introduced into the fuel stream follows a path of least resistance, which in the smooth bore well design, is an uninterrupted path close to the surface of the wall. In FIGS. 1 and 1A, small circles (xe2x80x9c∘xe2x80x9d) represent the air and dashes (xe2x80x9c--xe2x80x9d) represent the fuel. An emulsification is represented by a homogeneous distribution of air and fuel. As shown most clearly in FIG. 1A, the air drawn through the emulsion tube 28 mixes with the fuel only in a local or limited area close to the smooth walls of the main well 18. There are no provisions in the main well 18 to keep the air and fuel in a frothy emulsified state or to continuously direct, redirect or tumble the air back into the flowing fuel 8. Therefore, the air-fuel mixture remains primarily in a stratified form with only incomplete or partial emulsification of the fuel occurring at the areas where air enters air inlets or bleed holes 30 of the main well 18.
Other prior art is likewise not successful at fully emulsifying the air-fuel mixture. For example, U.S. Pat. No. 3,685,808 to Bodai describes a fuel delivery system that attempts to emulsify the fuel by introducing supersonic swirled air through a single air inlet positioned tangent to the end of the fuel nozzle. However, in actuality, the air does not swirl at all, but takes the shortest route by primarily flowing straight through and following the smooth contour of the fuel delivery tube. The air and fuel thus remain in a relatively stratified form. There will be some fuel aeration at the point where the non-swirling air enters the fuel delivery tube through the single air inlet. However, the complete air-fuel mixture is at best only partially aerated. U.S. Pat. No. 1,041,480 to Kaley purports to disclose a system that aggravates the intake air in the air channel down stream from the fuel nozzle. The wall of the intake air channel of the Kaley patent is threaded or knurled in an attempt to aggravate the intake air prior to mixing with the fuel. In reality, the knurled or threaded surface of the intake air channel causes an unwanted xe2x80x9cthrottlingxe2x80x9d effect thus restricting the flow or volume of air and fuel delivered to the combustion area.
U.S. Pat. No. 4,217,313 to Dmitrievsky et al. attempts to accomplish the creation of an air-fuel emulsion by trying to swirl air down-stream from a venturi. Air above the throttle valve, and at the same pressure as the upstream throttle chamber, passes around the throttle in a separate air passage to a circular air chamber below the venturi. Dmitrievsky teaches that the air pressures both above the throttle valve and in a separate air chamber below the venturi are higher than that of the down-stream throttle chamber. Therefore, the intake air above the throttle valve is supposedly forced into the air passage leading to the circular air chamber. Dmitrievsky presumes that the circular shape of the air chamber will cause the air to swirl vigorously and exit an annular passageway. A depression in the annular passage (venturi effect) then causes the air to move at sonic velocity. Dmitrievsky teaches that because the air is at sonic velocity and swirling, the invention achieves fine atomization and uniform mixing of the air and fuel. However, conventional testing has established that the swirling of air in such a configuration is almost non-existent. As a result, the air-fuel mixture will in all likelihood remain in the same stratified state as the mixture immediately down-stream of the venturi, and thus, is of very little benefit to fuel emulsification.
Italian Patent 434,484 to Bertolotti teaches a fuel/air mixing system that purportedly swirls the air within the main throttle area of the venturi. However, this system does little to promote fuel emulsion. Conventional flow bench testing has determined that any type of rough or threaded surface in the venturi region will only restrict the air flow through the venturi, thus slowing down the throttle response and reducing engine horsepower capabilities.
U.S. Pat. No. 1,969,960 to Blum relates to a drink dispenser used to aerate and mix a liquid drink. The Blum device attempts to mix and aerate the liquid by introducing two fluids (air and a drinking fluid) of equal pressures but different viscosity into a common chamber located above a dispenser nozzle containing a spiral band. However, because the liquids are of different viscosity, the volume of each liquid passing through the dispenser nozzle will be different. In practice, this causes the heavier liquid to separate unevenly from the thinner liquid, and little aeration of the drinking liquid occurs within the nozzle chamber. Most, if not all, of the aeration occurs at the sharp beveled end of the nozzle dispenser that forces the liquid from one side of the dispenser nozzle to the other side of the dispenser nozzle.
U.S. Pat. No. 2,034,430 to Farrow describes a carburetor system in which air enters a mixing chamber through a throttle valve. Within the mixing chamber is a cone having an apex faced in the direction of the main intake air. The surface of the cone is comprised of a grid of longitudinal ribs and a series of circular steps. Fuel enters the mixing chamber through a helix shaped passageway and distributes onto the surface of the cone""s ribs and steps. This is supposed to uniformly cover the cone with a thin liquid film of fuel separated into finely divided particles. When main air from the intake enters the mixing chamber, the fuel vaporzes, resulting in a homogeneous air-fuel mixture. This process, known as air stream atomization, does not use a secondary inlet air for fuel emulsification. However, the device does use a secondary idle air intake, but that has nothing to do with fuel emulsification.
U.S. Pat. No. 2,985,524 to Jacobus describes a device that attaches to the delivery side or lower end of the carburetor barrel. The device primarily consists of a nozzle body on the delivery side of the carburetor. The nozzle body that is comprised of a plurality of helical channels that purportedly cause the fuel to spiral or swirl before entering the venturi chamber. However, at no point is air introduced into this delivery system. Therefore, there is no possibility for increased air-fuel emulsification.
In diesel engine applications, fuel economy (i.e., efficient burning of the diesel fuel), is very important. Trucking companies go to great lengths to improve the economy of the over-theroad truck engines. An improvement of even small amounts results in significant savings in fuel costs. However, in diesel engine applications the diesel fuel is injected into either a manifold or the combustion chamber. There is no carburetor in diesel engines although there is an air delivery manifold. Thus, the diesel engine does not use a fuel emulsifier upstream of the injectors. Instead, fuel droplets are formed by the high pressure release of fuel from a small orifice. The droplets are directed into an air stream, which ultimately passes into the diesel combustion chamber.
It is the understanding of the inventor that in jet engines fuel is delivered into a combustion zone of the engine through a plurality of small orifices provided in a fuel delivery nozzle 20 of FIG. 6. The nozzle orifices are on the order of 0.004 inches in diameter. Fuel is pressurized and forced out these small orifices. The amount of fuel delivered is controllable, however the combustion process at high airflow velocities is inefficient. Some of the fuel is not burned before it is forced out the exhaust of the jet engine. No emulsification of the fuel is accomplished upstream of the fuel delivery nozzles as far as is known to the inventor. Based on the current representation of a jet engine as shown in FIG. 6 some air is delivered with the fuel from the fuel delivery nozzle 20.
In view of the above prior art, the need exists to improve fuel atomization in non-diesel engines as well as improve fuel efficiency in diesel engines by more effective emulsification of an air-fuel mixture or, in the case of diesel engines, provide an emulsified fuel/air mixture to the engine""s combustion chamber. The emulsification improvement system should have the ability to be easily and readily adapted into most existing fluid delivery systems. Although the specification is largely directed to improved emulsification systems and methods used in carburetors for internal combustion engines, the use of emulsion enhancing fuel delivery elements for use in jet engines is also contemplated. Furthermore, the invention is also applicable other systems where it is desirable to have enhanced emulsification, such as in diesel engines.
It is an object of this invention to provide an improved fuel emulsion device that is easily incorporated into existing carburetor systems.
It is an object of this invention to improve fuel emulsion and negate fuel stratification by introducing air into the fuel delivery portion of the carburetor through an elongated and threaded fuel channel.
It is a further object of this invention to improve fuel emulsion and negate fuel stratification by causing the air-fuel mixture to roil and tumble to form a frothy emulsion.
It is another object of this invention to improve fuel emulsion by passing the air-fuel mixture over threaded or other knurled surfaces, or over bumps, protrusions, cavities or dimples, before introducing the mixture into the venturi portion of the carburetor.
It is another object this invention to improve fuel emulsion by confining the air/fuel mixture within the main fuel well by using a straight helix or spiral shaped insertion rod that enhances the tumbling of the air/fuel mixture.
It is another object of this invention to provide emulsified fuel to the combustion chamber of a diesel engine.
It is an object of this invention to improve engine performance and fuel economy by providing better and faster combustion of the fuel.
It is a further object of this invention to provide faster and more efficient combustion, thus allowing for a reduction of heat on component contact surfaces and reduction of engine cooling requirements.
It is an object of this invention to provide combustion that is more efficient and to diminish the occurrence of unburned fuel in the combustion exhaust.
It is an object of this invention to reduce the emissions from gasoline or diesel engines by more thorough and efficient combustion of fuel.
It is an object of this invention to improve fuel and airflow through a carburetor by optimizing the position of a booster in the throat of a carburetor.
It is also an object of this invention to optimize fuel and airflow through a carburetor by making the position of the booster adjustable in the throat of the carburetor.
It is another object of the invention to improve fuel and airflow through a restricted carburetor by fitting a flow enhancing apparatus over the intake area of the carburetor.
It is an object of the invention to enhance the flow characteristics of a restricted carburetor by fitting over the intake areas of the carburetor an apparatus that relocates the position of the venturies in the carburetor.
It is an object of this invention to promote air-fuel emulsion for engines that use fuel injection systems to supply fuel to the combustion chamber, including both gasoline and diesel engines.
It is an object of this invention to improve air-fuel emulsion for jet or turbine engines.
It is also an object of this invention to provide an emulsion enhancing fuel nozzle that includes an adjustable air inlet element.
It is another objective of the invention to provide a fuel nozzle that enhances air-fuel emulsion over a wide range of airflow rates and at a range of altitudes and air densities in which a jet engine routinely operates.
It is another object of this invention to provide a fuel nozzle for use in a jet engine or similar applications that enhances emulsification and is formed as a multi-port structure that is machined and assembled, thereby allowing inexpensive construction of a complex internal configuration.
It is an object of this invention to promote air-fuel emulsion for propane engines or natural gas heaters.
It is an object of this invention to promote emulsion formation for paint sprayers.
It is an object of this invention to promote emulsion formation for perfume dispensers.
The above and other objects are achieved by a method for mixing two fluids. The method comprises the acts of passing a first fluid through a primary passage and mixing a second fluid with the first fluid. The second fluid is mixed with the first by introducing it to the primary passage through an inlet located upstream in the primary passage. The mixture of fluids is then further emulsified by passing it over at least one obstruction located within the primary passage down stream of the inlet. In the preferred embodiment of the method, first fluid is combustible fuel and the second fluid is air. To increase the mixing effect, the second fluid may be introduced to the first fluid through a plurality of inlets to the primary passage, and the mixture is passed over a threaded interior surface within the primary passage. Ideally, the threaded interior surface is formed on a portion of the wall of the passage extending downstream between and after each inlet. The emulsifying effect of the present invention is enhanced by restricting the volume of the primary passage to maintain the mixture within a reduced area as it passes over the obstruction(s).
The above and other objects are also achieved by a system for emulsifying a primary and secondary fluid. The system includes a passage for the primary fluid and an inlet for the secondary fluid. The inlet is located upstream in the passage. An obstruction within the passage is located downstream of the inlet for the secondary fluid. In its preferred form, the passage comprises a fuel well leading to a venturi, the inlet for the secondary fluid comprises an air inlet and the obstruction comprises a plurality of raised protrusions extending from an inside surface of the fuel well into the path of the fuel. For example, the plurality of raised protrusions may comprise threads formed on the inside surface of the fuel well. In a modification of the system, a restrictor is placed within the volume of the fuel well. The restrictor may comprise a length of threaded rod placed parallel to the fuel well walls.
The above-described methods and systems have application not only for internal combustion engines, both gas and diesel, but also furnaces, jet engines and other areas where complete emulsification of the two mixtures is desired. In addition, the obstructions in the fuel passages may take any of several forms, including threads, knurls, bumps, protrusions, dimples, cavities, indentations and the like. Also, it is not required that the obstructions, bumps, protrusions, dimples, cavities, indentations etc. be located only in the main well where liquid fuel and air are first mixed and emulsified. These obstructions, bumps, protrusions, dimples, cavities, indentations etc. can be located in any passage or emulsified fuel/air delivery system that contains both air and fuel being delivered to a combustion chamber. For instance, the obstructions and so forth could be in the main delivery tube or main nozzle or in the inside of the booster venturi downstream of the main nozzle. Furthermore, the obstructions can be anywhere downstream of any point where there is a mixing of a liquid and a gas.
The above and other objects are achieved in an embodiment of the invention applicable to jet engines, wherein the fuel delivery and emulsifier nozzle includes a flared portion having an increased diameter relative to the initial or upstream section of the nozzle. In the preferred form of this embodiment, the emulsifier nozzle in a jet engine comprises a plurality of air inlets along the initial straight and subsequent flared portion of the nozzle. This nozzle may also comprise a turning zone toward the exhaust end of the nozzle wherein the fuel and air emulsion passing through the nozzle may be directed toward a preferred path.
The above and other objects are achieved in an embodiment of the invention applicable to diesel engines and four cycle gasoline engines, wherein a quantity of emulsified fuel is prepared in a carburetor and delivered through the air intake manifold to the combustion chambers of the engine. A fuel charge of injected fuel augments the quantity of emulsified fluid delivered to the engine by a conventional intake manifold.
The above and other objects are also achieved by adjusting the position of the venturi booster (also referred to herein as the xe2x80x9cboosterxe2x80x9d), in the throat of the carburetor relative to the venturi (xe2x80x9cventurixe2x80x9d refers to the narrow internal diameter of the carburetor throat) to optimize the effect of the venturi. In a modified form of this embodiment, the booster is mounted in the throat of the carburetor so that its position is adjustable.
The above and other objects of the invention are also achieved by forming an insert to be placed over the carburetor and having a number of air runners corresponding to the number of runners or carburetor throats in the host carburetor. Each runner of the insert can have a constant diameter throat, or can alternatively have decreasing or increasing throat dimensions. In one embodiment the throats of the insert can be a venturi therein that either augments, effectively repositions, blends with or replaces a standard venturi in a standard location in the throat of a carburetor. By altering the location of the venturi to the location of the optimum signal (for drawing an optimum mixture of emulsified fuel into the intake flow stream) the highest efficiency of the carburetor can be attained.
The preferred embodiments of the inventions are described in the following Detailed Description of the Invention. Unless specifically noted, the words and phrases in the specification and claims are intended to have their ordinary and accustomed-meaning to those of ordinary skill in the applicable arts. If any other meaning is intended, the specification will specifically state that a special meaning is being applied to a word or phrase. Likewise, the use of the words xe2x80x9cfunctionxe2x80x9d or xe2x80x9cmeansxe2x80x9d in the Detailed Description is not intended to indicate a desire to invoke the special provisions of 35 U.S.C. Section 112, paragraph 6 to define the invention. To the contrary, if the provisions of 35 U.S.C. Section 112, paragraph 6, are sought to be invoked to define the inventions, the claims will specifically state the phrases xe2x80x9cmeans forxe2x80x9d or xe2x80x9cstep forxe2x80x9d and a function, without also reciting in such phrases any structure, material, or act in support of the function. Even when the claims recite a xe2x80x9cmeans forxe2x80x9d or xe2x80x9cstep forxe2x80x9d performing a function, if they also recite any structure, material or acts in support of that means of step, then the intention is not to invoke the provisions of 35 U.S.C. Section 112, paragraph 6. Moreover, even if the provisions of 35 U.S.C. Section 112, paragraph 6, are invoked to define the inventions, it is intended that the inventions not be limited only to the specific structure, material or acts that are described in the preferred embodiments, but in addition, include any and all structures, materials or acts that perform the claimed function, along with any and all known or later-developed equivalent structures, materials or acts for performing the claimed function.